A study on available technologies to treat asbestos L. T omassetti - - PowerPoint PPT Presentation

▶
a study on available technologies to treat asbestos
SMART_READER_LITE
LIVE PREVIEW

A study on available technologies to treat asbestos L. T omassetti - - PowerPoint PPT Presentation

Oct 08, 2022 482 likes •714 views

A study on available technologies to treat asbestos L. T omassetti 1 , V. Paolini 1 , M.Segreto 1 , M. T orre 1 , D. Borin 1 , P . T ratzi 1 , F . Petracchini 1 , Presenting author: Laura Tomassetti 7TH INTERNATIONAL CONFERENCE ON SUSTAINABLE

slide-1
SLIDE 1

A study on available technologies to treat asbestos

7TH INTERNATIONAL CONFERENCE ON SUSTAINABLE SOLID WASTE MANAGEMENT 26-29 June 2019, AQUILA ATLANTIS HOTEL Heraklion, Crete Island, Greece

  • L. T
  • massetti1, V. Paolini1, M.Segreto1, M. T
  • rre1, D. Borin1, P

. T ratzi1, F . Petracchini1, Presenting author: Laura Tomassetti

1

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-2
SLIDE 2

Asbestos EU Raccomandations Inertization Technical solutions Conclusions

Summary Summary

2

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-3
SLIDE 3

ASBESTOS: is a group of minerals composed by a natural mineral fjbres The fjbrous-asbestiform crystal habit and chemical-physical surface reactivity, may induce fatal lung diseases.

What is the asbestos? What is the asbestos?

3

Giacobbe at al., 2010

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-4
SLIDE 4

According to current legislation, ACW (Asbestos Containing Waste) must be removed and properly managed in accordance with safety regulations. The European Parliament resolution 2012/2065 (INI) of 14 March 2013 (“asbestos related occupational health threats and prospects for abolishing all existing asbestos”) states that: “whereas delivering asbestos waste to landfjlls would not appear to be the safest way of defjnitively eliminating the release of asbestos fjbres into the environment (particularly into air and groundwater) and whereas therefore it would be far preferable to opt for asbestos inertization plants”. “creating landfjlls for asbestos waste is only a temporary solution to the problem, which in this way is left to be dealt with by future generations”

European Parliament resolution European Parliament resolution

4

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-5
SLIDE 5

Inertization: The treatments aim to completely modify the crystallochemical structure of asbestos therefore eliminate the danger.

What’s the solution? What’s the solution?

5

Gualtieri et. Al, 2000

slide-6
SLIDE 6

All the intertization processes can be classifjed into the following three macro-categories: Thermal treatment – consist of the modifjcation of the crystal-chemical structure, through the use of heat up to or above 1200 °C Three stages:

  • loss of adsorbed water,
  • removal of structural OH groups
  • crystallization of amorphous materials

Chemical treatment– consist to use strong basic or acid solutions to convert asbestos into harmless compounds Mechanochemical treatment – fjbres are degraded by mechanical milling

What’s the solution? What’s the solution?

6

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-7
SLIDE 7

Inertization: Thermal treatment Inertization: Thermal treatment

This category is very articulated and incorporate the most important industrial experiences.

7

The main advantages connected to thermal treatment are:

  • incorporation of large

amounts of heavy metal ions inside an inorganic amorphous network;

  • the fjnal process product is

inert

  • fmexibility to treat wastes of

various type;

  • a reduced amount of

waste is obtained.

  • consolidated technology;

The common critical issues for all thermal treatments are:

  • the high energy required

to heat a thermally inert material such as asbestos.

  • formation of atmospheric

pollutants during the heating phases (vinyl- asbestos can lead to the formation of persistent

  • rganic pollutants such as

dioxins and polychlorinated biphenyls)

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-8
SLIDE 8

Inertization: Thermal treatment Inertization: Thermal treatment

Simple Vitrifjcation - simplest thermal treatment at temperatures generally above 1000 °C to obtain an inert silica material. The resulting is the production of an inert glass material. Vitrifjcation with controlled recrystallization – the only difgerence to simple vetrifjcation is that a heating rate control system is applied. Is it possible to obtain products with good mechanical properties which can be used in building or civil works.

8

INERTIAM Process– First operative plant which uses a plasma torch KRY

  • AS Process – The cooking cycle uses a

“tunnel” continuous industrial gas oven There are real industrial applications

slide-9
SLIDE 9

Inertization: Thermal treatment Inertization: Thermal treatment

Thermal treatment with other inorganic materials in addition to the controlled

  • Recrystallization. it is possible to use inorganic materials such as clay

to produce expanded clay

9

CORDIAM Process– ACW is weted, mixed with clay, milled and then roasted in the

  • ven.

VETRIFIX Process – The ACW is milled and mixed with glassy granules and glass

  • scraps. After is added

a low-melting agent and then inserted in electric oven.

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

At present technology is at a pilot plant leve

slide-10
SLIDE 10

Inertization: Thermal treatment Inertization: Thermal treatment

  • Treatment

with Oxyhydrogen – provides the use

  • f

a stoichiometric gas mixture of 1:2 oxygen and hydrogen (oxyhydrogen) produced by water electrolysis.

10

Microwave air plasma treatment uses microwave as energy. There is no signifjcant use of this technique on an industrial scale, with the exception of ATON HT process.

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-11
SLIDE 11

Chemical treatment consists in treatment of the compounds included in asbestos structure with chemical additives (strong basic or acid) which are added to lower the melting temperature or enhance mineralogical decomposition.

Inertization: Chemical treatment Inertization: Chemical treatment

11

The main advantages connected to chemical treatment are:

  • the reduced energy cost
  • room temperature process

The common critical issues for all chemical treatments are:

  • the long treatment time
  • the

need

  • f

waste liquid treatment

  • the costs associated with the

consumption of reagents and the subsequent disposal

  • f

wastewater. .

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-12
SLIDE 12

Inertization: Chemical treatment Inertization: Chemical treatment

  • Classic chemical treatment
  • Use high pH (alkaline conditions) ,asbestos is converted into

magnesium hydroxide and sodium silicate

  • Use acid solutions, strong acidic solutions can hydrolyse the Si–O

bond, creating free silanol moieties(R3Si–OH).

  • Use Hydrofmuoric acid to form gaseous silicon fmuoride (SiF4)

12

There aren’t real industrial applications

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-13
SLIDE 13

Inertization: Chemical treatment Inertization: Chemical treatment

  • Hydrothermal treatment (supercritical water)

This treatments eliminates the problem of the handling of corrosive/hazardous reagents because this approach allows to

  • perate at neutral pH.

It uses supercritical water at 250 MPa and 650 °C. The main issues related to the process are:

  • particularly high pressures;
  • fjltration of the obtained water,
  • need (in some specifjc applications) to add 6% of hydrogen

peroxide.

13

The process requires the addition of a reducing agent such as a metal in its elementary state. Criticalities of these processes are linked to the onset of reaction. The advantage of this approach is that oxidation–reduction reactions are preferred and once started they proceed spontaneously.

  • Treatment with reducing agents

At present, technology is at a prototype level

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-14
SLIDE 14

Inertization: Mechanochemical treatment Inertization: Mechanochemical treatment

14

Mechanochemical treatment The mechanochemical treatments rely on the mechanical energy transmitted to the ACW by crushing machines the task of destroying the crystal lattices and the molecular bonds present in asbestos. High-energy milling

  • r

ultramilling processes have been successfully proposed and used at the real and laboratory scale to handle the ACW. The results are

  • btained

from progressive amorphization by the release

  • f the hydroxyl ions needed to maintain

the crystalline structure: with this regard, the process is called “cold vitrifjcation”.

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-15
SLIDE 15

Comparison of the difgerent treatments Comparison of the difgerent treatments

15

Parameters Thermic Chemical Mechanochemic al Process temperature (°C)

1000-1800 <600 <100

Energy consumption

high low medium

Waste products

high quantities of waste gasseous high quantities of waste water no waste

Reuse

Application for road surface or cement Application in cement or glass industry Application in civil engineering applications in building materials

Atmospheric emissions

high low low

Wastewater

low quantities high quantities of wastewater none

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-16
SLIDE 16

Conclusion Conclusion

16

The level of some technologies is able to tackle the problem of asbestos-containing materials. Indeed a number of applications is available for thermal degradation of asbestos. Each technology presents advantages and disadvantage and can be selected on the base of the specifjc process needs. The possibility to obtain a reusable byproduct is the most important technical point in order to reach the economic feasibility of a plant.

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-17
SLIDE 17

17

Thank you for your attention

Laura Tomassetti National Research Council of Italy Institute of Atmospheric Pollution Research laura.tomassetti@iia.cnr.it

http://www.fjlieraamianto.it/

slide-18
SLIDE 18

18

Laura Tomassetti National Research Council of Italy Institute of Atmospheric Pollution Research laura.tomassetti@iia.cnr.it

http://www.fjlieraamianto.it/

slide-19
SLIDE 19

Recycling Recycling

19

the output material as second raw material studied by Gualtieri et. al (2011a, 2011b, 2012) Viani et al (2013, 2014) are:

  • Ceramic pigments industry;
  • Production of ceramic and glass ceramic frits;
  • Ceramic tile industry;
  • Brick industry;
  • Glass industry for the production of synthetic fjbers;
  • Production of cement materials;
  • Geopolymer
  • Plastic industry;

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

Polipropilenic compound Brick Glaze Concrete

slide-20
SLIDE 20

Recycling Recycling

20

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300

slide-21
SLIDE 21

Recycling Recycling

21

National Research Council of Italy Institute of Atmospheric Pollution Research Via Salaria km 29.300